Pushing the Limits of Electrical Detection of Ultralow Flows in Nanofluidic Channels

Micromachines

Klaus Mathwig¹ 

[1] MESA+ Institute for Nanotechnology, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands; E-Mail

关键词: flow detection;    electrochemical sensor;    nanofluidics;    cross-correlation;    nanochannel;    redox cycling;   

DOI  :  10.3390/mi4020138

来源: mdpi

【 摘 要 】

This paper presents improvements in flow detection by electrical cross-correlation spectroscopy. This new technique detects molecular number fluctuations of electrochemically active analyte molecules as they are transported by liquid flow through a nanochannel. The fluctuations are used as a marker of liquid flow as their time of flight in between two consecutive transducers is determined, thereby allowing for the measurement of liquid flow rates in the picoliter-per-minute regime. Here we show an enhanced record-low sensitivity below 1 pL/min by capitalizing on improved electrical instrumentation, an optimized sensor geometry and a smaller channel cross section. We further discuss the impact of sensor geometry on the cross-correlation functions.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland.